[Ffmpeg-devel-irc] ffmpeg.log.20130928

burek burek021 at gmail.com
Sun Sep 29 02:05:01 CEST 2013


[00:37] <bffmpeg> skifreak: http://www.ffmpeg.org/download.html  search for "static builds", see if you can find a suitable version that was built in the last day or so
[00:42] <skifreak> bffmpeg: thanks for the help. In gentoo right now, running v2.0.1. Can easily installed the live ebuild in the package manager, or if you still think it's better, I can install the latest static build in http://ffmpeg.gusari.org/static/64bit/
[00:43] <bffmpeg> skifreak: things change fast here, so if you can quickly build a recent package, do so
[00:44] <bffmpeg> if you remain stuck, the devs are very responsive if you can clearly articulate your issue - see http://ffmpeg.org/trac/ffmpeg
[00:45] <skifreak> bffmpeg: will do, always glad to see fast progress. Compiling the live version of ffmpeg now
[00:45] <skifreak> thanks, I'll definitely look into that. It's been a few months, but I've submitted bug reports before
[00:47] <bffmpeg> skifreak: see also http://ffmpeg.org/trac/ffmpeg/wiki/How%20to%20quickly%20compile%20libaacplus
[00:50] <skifreak> bffmpeg: thanks for all of the links and help. I currently don't have libaacplus installed (wonder if I should...I use ffmpeg primarily for compressing bluray material)
[00:50] <JEEBsv> libaacplus shouldn't be recommended any more if it ever was, fdk-aac can do what it can, and more
[00:51] <JEEBsv> and it is similarily "nonfree", so it's really in a very, very similar position, just that it can do it all better
[00:51] <JEEBsv> (and more, libaacplus is HE-AAC(v2) only
[00:51] <bffmpeg> ^^^^^ what jeebs sez
[00:51] <skifreak> thanks guys!
[00:51] <bffmpeg> jeebs == da shiz
[00:52] Action: skifreak is glad he's able to speak to some pros
[00:53] <skifreak> JEEBsv: thanks. Currently I'm not compressing bluray audio, usually it doesn't take up much space...though pcm tends to be a little large....
[00:53] <JEEBsv> I just saw libaacplus linked :P
[00:53] <skifreak> insight is always appreciated
[00:54] <skifreak> compiled the life version of ffmpeg (ffmpeg-9999) and same results as before
[00:54] <skifreak> (with the right 3D bluray passthrough file) http://dpaste.com/1398445/
[00:56] <skifreak> should I submit a bug report then, or do either of you want to look at samples of the left (playable even with mplayer2) or right (errors out on analyzation) videos first?
[01:02] <bffmpeg> skifreak: "Could not find codec parameters for stream 0 (Unknown: none (HDMV / 0x564D4448)): unknown codec"   What's the source of   right.m2ts
[01:04] <skifreak> bffmpeg: It's a passthrough bluray rip of Immortals 3D (DVDFab)
[01:13] <skifreak> bffmpeg: I would really like to test the right file out with another program to see if it's playable, but if ffmpeg/mplayer fails, what other options do I have?
[01:13] <bffmpeg> skifreak: not a dvdfab expert, but do you have the option to turn the codec info on/off. i.e. are you sure the codec info is in the m2ts file?
[01:14] <skifreak> bffmpeg: accord to mediainfo it is http://dpaste.com/1398454/
[01:15] <skifreak> the left video file according to mediainfo, for comparison http://dpaste.com/1398455/
[01:17] <skifreak> was even wondering if I could force ffmpeg to use a very specific codec, using the exact same one with the same parameters as the left video file. I've had no success on this end so far either
[01:18] <skifreak> definitely open to using something else other than DVDFab, but it seems to work the best on anything I throw at it (runs smoothly in wine)
[01:18] <bffmpeg> skifreak: mediainfo seems to see it
[01:19] <skifreak> that's what I thought, though I'm no expert on ffmpeg and how codecs are recognized
[01:19] <bffmpeg> i would say file your original post, with your mediainfo page, as per the trac page. There is an ftp service (see trac) to upload your file
[01:19] <skifreak> bffmpeg: cool, definitely will do. Should a 10MB sample of each suffice?
[01:19] <bffmpeg> yes
[01:21] <skifreak> cool, thanks a lot for your help. I know bluray is a little weird with how it passes 3D, but I'm looking forward to finally compressing passthrough 3D (have been forced to use DVDFab's own parameters and codecs up until now on 3D files, stuck at using a constant bit rate instead of CRF)
[01:22] <bffmpeg> give it a crisp title such as : AVC codec in m2ts file not recognized by ffmpeg
[01:23] <bffmpeg> if you file correctly the ticket should pop up here
[01:23] <skifreak> bffmpeg: thanks, I'm pretty green at submitting bug reports and proper titles and descriptions do take a small amount of time to learn
[01:25] <skifreak> will file the bug tonight, need to fill a void in my stomach first and tear apart some muscle fiber first
[02:34] <omega_terry> hi there. trying to download a live youtube stream. getting a 403 error. think i'm using the wrong m3u8 file
[02:35] <omega_terry> http://www.youtube.com/watch?v=Bht5_9sUg3k&hd=1
[02:36] <omega_terry> http://pastebin.com/qJiWhTN5
[02:38] <omega_terry> that's mine
[02:39] <omega_terry> here's a working example
[02:39] <omega_terry> http://pastebin.com/XnVBTqKF
[02:56] <sine``> whats the syntax for -vc none
[02:56] <sine``> its changed since time ago
[02:56] <sine``> more shorthand no
[02:56] <sine``> now
[02:57] <sine``> 0?
[03:04] <klaxa> -nv
[03:04] <klaxa> *-vn
[03:05] <sine``> and what about copy audio
[03:34] <klaxa> -c:a copy
[04:21] <defaultro> hey guys, how come my local copy of video is very clean using qp=0 but once I uploaded it to youtube, there's tons of image quality lost
[04:52] <skifreak> bffmpeg: about to submit the bug. Do you want me to upload the left video file (the one which ffmpeg has no problem analyzing) as well or just the right video file (the problem file)?
[05:56] <skifreak> Submitted ticket #3009 (https://trac.ffmpeg.org/ticket/3009). Thanks all for the support
[06:30] <Niatross> Will the dca codec ever come out of the "experimental" phase ("-strict -2")?
[09:28] <skifreak> I know this was just submitted, and only recently reviewed, but can someone tell me why ticket #3009 (https://trac.ffmpeg.org/ticket/3009) is an enhancement, not a defect? (The priority of wish seems a little low, but that's just me)
[10:46] <Willdude123> Is there a way in FFmpeg to keep the aspect ratio but decrease the quality of a video by some percentage?
[10:58] <skifreak> Willdude123: I don't know what your end goal is exactly, but i use the crf option through x264 in ffmpeg to accomplish different amounts of change in "perceived quality"
[10:59] <Willdude123> skifreak, well basically I have a 720p video, and I want to scale the quality down so that the stream doesn't lag.
[11:01] <skifreak> Willdude123: do you mean decrease the resolution?
[11:01] <skifreak> or just make the file smaller?
[11:01] <Willdude123> Yes, I think I do. Well I want to do anything that I can to make the stream not lag as much due to my slowish internet
[11:02] <skifreak> ah, ok, well I'd recommend using the same res for now, and decreasing the quality of the video, though you could do both
[11:03] <skifreak> as far as crf goes: example: ffmpeg -i <input> -c:v libx264 -crf <number> <output> explanation and possible crf values: http://mewiki.project357.com/wiki/X264_Settings#crf
[11:04] <Willdude123> Okay...
[11:04] <Willdude123> I don't completely understand that but I'll work on it.
[11:05] <skifreak> crf just changes the perceived quality (example: blurring frames together in action sequences, where sharpness matters less)
[11:06] <skifreak> as far as changing the resolution: http://mewiki.project357.com/wiki/X264_Settings#resize
[11:07] <Willdude123> Okay. So what possible crf values are there?
[11:07] <skifreak> you can pass any x264 options through to ffmpeg the same way crf is above (make sure to put them after -c:v libx264 and before any other stream changes, such as audio, -c:a, or subtitle, -c:s, and most certainly before the output file)
[11:08] <skifreak> 0 to 51 http://slhck.info/crf.html
[11:08] <Willdude123> Oh to change the res I was using -s
[11:08] <skifreak> the lower the number the better the quality
[11:09] <skifreak> well, whichever way to want to handle it. I prefer to use x264, seems it's one of the best video codecs out there
[11:10] <skifreak> I encode transparent quality 1080p files with a crf value of 18. Transparent being the same perceived quality as the source.
[11:12] <skifreak> for kicks, here's an example of the command I use all of the time ffmpeg -i <input> -map 0 -c:v libx264 -vf crop=<crop values> -crf 18 -tune film -preset slower -profile:v high10 <output>
[11:12] <skifreak> you probably don't need -vf crop=<crop values>, since you're not cropping
[11:13] <skifreak> just a few different settings to make you aware of and play around with
[11:17] <Willdude123> Actually, my internet is too crap to stream it even with awful quality
[11:17] <skifreak> ok, well, good luck never the less
[11:25] <Willdude123> skifreak, thanks. http://imgur.com/QvPNnxy
[11:25] <Willdude123> It buffers for about 5 seconds every 15 seconds but nvm, it was an interesting project.
[11:27] <skifreak> Willdude123: no problem, sorry it didn't pan out for you. Glad I could be of some help.
[11:28] <Willdude123> skifreak, it kinda sometimes works OK. It was more just a project to do than something I actually expected to work.
[11:28] <Willdude123> I guess UDP streaming may be a bit faster.
[11:29] <skifreak> Willdude123: good to experiment though. I have no clue on streaming of any kind.
[11:30] <Willdude123> Cool. I'm working on something that should let me start a torrent downloading in the morning and then watch it during my lessons that happen to involve working with computers.
[11:32] <Willdude123> Perhaps I need a VPS with faster interwebz
[11:33] <skifreak> well you did say your bandwidth was the limitation. Shame that upstream has such little priority in consumer ISPs.
[11:37] <skifreak> Take care Willdude123, I'm going to sleep while watching some Corpse Bride and hope the new bug I submitted is resolved at some point.
[11:37] <Willdude123> Night! Thanks a lot for the help.
[11:38] <skifreak> No worries, glad I could shed some light. It's nice to be on the other side of the help desk for a change
[18:05] <burek> hi :)
[18:06] <burek> here is one interesting question imho: "Can ffmpeg detect an overall "lightness" level in a photo?" -> http://ffmpeg.gusari.org/viewtopic.php?f=16&t=1076
[18:07] <durandal_1707> and how would such info be exposed to user?
[18:07] <durandal_1707> is that some number in some units?
[18:08] <burek> i guess it's an illumination
[18:09] <burek> http://en.wikipedia.org/wiki/Lux
[18:10] <burek> but since it's a still image, probably some arithmetic middle could be calculated for all pixels
[19:05] <burek> is it possible to specify pix_fmt in ffserver.conf
[19:06] <burek> or even better is there any way to get the list of all supported options that can be used in ffserver.conf file?
[19:07] <burek> i found this, i hope it hasn't changed https://trac.ffmpeg.org/ticket/2954
[19:57] <burek> is there any good page that explains the relation between -maxrate, -minrate and -bufsize, because there are several duplicate questions about it, where people in general lack the understanding of that relation and as a result use them in a wrong way
[20:09] <burek> this question is a typical one of that kind http://ffmpeg.gusari.org/viewtopic.php?f=11&t=1063
[21:00] <shevy> hmm got a question
[21:00] <shevy> let's assume I have two .mp3 files
[21:00] <shevy> both may have ' ' as part of the character name. I am using linux + bash right now
[21:00] <shevy> I use this commandline:
[21:01] <shevy>   ffmpeg -i concat:"foo bar.mp3"\|" bla ble.mp3" -acodec copy output.mp3
[21:01] <shevy> this seems to work, the resulting output.mp3 plays fine. but is this the right syntax to use for concat: ? it looks strange...
[21:25] <burek> ShadowJK
[21:25] <burek> oops shevy
[21:26] <burek> the backslash \ escapes the pipe character, so it's ok
[21:26] <shevy> ok
[21:26] <burek> concat: will look for the value after the colon : so, it's good :)
[22:03] <BlackBishop> any recommended opts to fastly convert from a fullhd mkv(x264/aac) to something flv supported ( @640:480 ) ?
[22:06] <BlackBishop> or even 320x240 .. just need it to be fast .. my nvidia ion can decode the mkv fast enough .. but I can't make it encode to flv fast enough ..
[22:08] <BlackBishop> -vcodec flv -ac 1 -acodec mp3 -ar 44100 -f flv gets me @ 13fps :|
[22:29] <BlackBishop> maybe make vdpau help somehow .. :|
[22:51] <relaxed> BlackBishop: no
[22:51] <relaxed> a faster cpu will
[23:41] <burek> BlackBishop, why not using -vcodec libx264 -f flv
[23:45] <sacarasc> Because he wants encoding speed.
[23:45] <sacarasc> I suppose -preset ultrafast might work well.
[00:00] --- Sun Sep 29 2013


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